FRANKLIN TOWNSHIP, Mich. (AP) — Investigators have discovered human remains during a search of property in southeastern Michigan that belongs to a man whose wife disappeared more than three years ago and is presumed dead.

Dee Warner’s family reported her missing in April of 2021. Her husband, Dale John Warner, 56, was charged in November with open murder and tampering with evidence in her disappearance. He has pleaded not guilty.

Michigan State Police said in a statement Sunday that they recently searched Dale Warner’s property in Lenawee County and found human remains.

“The remains are currently in the process of being recovered and there will be a great deal of work and testing completed before positive identification is made,” the agency said in a social media post. “The family of Dee Warner has been contacted and advised of the findings. This continues to be an ongoing investigation.”

Family members told WTVG-TV and WTOL-TV that the remains were found Friday in a sealed, empty tank meant for anhydrous ammonia, which is used as fertilizer for crops.

An autopsy is scheduled for Tuesday.

Dee Warner was 52 when she was last seen the morning of April 25, 2021, on a road in Franklin Township, about 70 miles (110 kilometers) southwest of Detroit. Since then, she has had no contact with her family or friends.

Dale Warner remains held in the Lenawee County Jail. He is scheduled to appear in court Sept. 4 for a pretrial hearing.

“We believe that a fair and objective review of the evidence — or more precisely the lack of evidence in this case — will show that Mr. Warner did not kill his wife,” his attorney, Mary Chartier, told The Associated Press when he was charged in November.